public class Trapezia
    {
        public Trapezia()
        {
        }

        public Trapezia(decimal sd,decimal xd,decimal g,decimal y)
        {
            this.Sd = sd;
            this.Xd = xd;
            this.G = g;
            this.Y = y;
        }

        private decimal _sd;
        public decimal Sd
        {
            get
            {
                return _sd;
            }
            set
            {
                _sd = value;
            }
        }

        private decimal _xd;
        public decimal Xd
        {
            get
            {
                return _xd;
            }
            set
            {
                _xd = value;
            }
        }

        private decimal _g;
        public decimal G
        {
            get
            {
                return _g;
            }
            set
            {
                _g = value;
            }
        }

        private decimal _y;
        public decimal Y
        {
            get
            {
                return _y;
            }
            set
            {
                _y = value;
            }
        }

        public decimal Mianzhi()
        {
            return (Sd + Xd) * G / 2;
        }

        public decimal Zhouchang()
        {
            return Sd + Xd + 2 * Y;
        }
    }